The present invention relates to a photographic processing apparatus which exposes photographic papers using a laser beam modulated based on image data.
Recently, a photographic processing apparatus which adopts a so-called digital exposure method has been popularly used. In such a digital exposure method, a photographic papers are exposed by light modulated based on digital image data. By adopting the digital exposure method, various types of image processes such as color correction, concentration correction and sharpening processing can be performed with the high degree of freedom and, at the same time, a rapid additional printing processing can be realized. Further, it is possible to obtain prints of high quality which are excellent in the reproducibility of color and concentration and resolution.
As one type of such a digital exposure method, there has been known a scanning exposure method which exposes the photographic papers with a modulated laser beam scanned using a polygon mirror or the like. In a current situation, however, the photographic processing apparatus adopting the scanning exposure method cannot change the intensity of the laser beam which are outputted in a stable manner from a laser beam emitting device and hence, the photographic processing apparatus can only cope with the photographic paper having specific coloring characteristics. Accordingly, when a photographic paper having coloring characteristics different from the specific coloring characteristics is used, the quality of images formed on the photographic papers is largely deteriorated.
It is a primary object of the present invention to provide a photographic processing apparatus which can properly expose a plurality of types of photographic papers having coloring characteristics different from each other in conformity with these coloring characteristics.
With respect to the photographic processing apparatus of the present invention, the photographic processing apparatus which exposes photographic papers using a laser beam modulated based on image data includes a laser beam emitting device and changeover means for changing over the intensity of a laser beam outputted from the laser beam emitting device in a plurality of levels.
According to this photographic processing apparatus, since the intensity of the laser beam can be changed over in a plurality of levels, it is possible to properly expose photographic papers which differ in color characteristics from each other and the number of types of paper is equal to the number of changeover levels of the intensity of the laser beam. Here, it is preferable that the changeover means is adjusted in advance such that the intensity of the laser beam outputted from the laser beam emitting device at respective levels exhibits a small and stable change rate with respect to an environmental factor such as temperature.
From a viewpoint of obtaining prints of high quality by stabilizing the intensity of laser beams, it is preferable that the photographic processing apparatus of the present invention is further provided with stabilizing means which is for stabilizing the intensity of the laser beam outputted from the laser beam emitting device.
It is preferable that the photographic processing apparatus of the present invention further includes a filter which is for reducing the intensity of the laser beam outputted from the laser beam emitting device and a filter control means which is for changing over a laser intensity reduction rate obtained by the filter in a plurality of levels.
The intensity of the laser beam depends not only on an input power to the laser beam emitting device but also on the environmental factors such as temperature and hence, in stabilizing the intensity of the laser beam using only one level, it has been necessary to frequently perform a complicated tuning process. To the contrary, by adopting the above-mentioned construction, it is possible to divide the respective intensities of the laser beams so that each laser beam is out putted from the laser beam emitting device into a plurality of levels using a filter. Accordingly, it is unnecessary to additionally perform the complicated tuning process for increasing the number of changeover levels of the intensity of the laser beam outputted from the laser beam emitting device. Thus, it is possible to properly expose a larger number of types of printing papers which differ in coloring characteristics
Further, it is preferable that the photographic processing apparatus of the present invention is configured such that changeover means changes over the intensity of the laser beam outputted from the laser beam emitting device at two to five levels. Due to such a construction, the number of changeover levels of the intensity of the laser beam is relatively small, that is, 2 to 5 and hence, the tuning operation of the laser beam emitting device can be reduced.
Other and further objects, features and advantages of the invention will appear more fully from the following description taken in conjunction with the accompanying drawings.